Rheostat



Patented Nov. 27, 1923.

' UNITED STATES PATENT OFFICE.

winmx s'run'r wnBsrEn, or BRIGHTON, MASSACHUSETTS.

nnnos'rnr. l

Application Med November 20, 1920. Seriallo. 425,371.

yfor an object thereof to provide a device of this character which willpermit better ventilation than is possible with rheostats now known.

Another structural advantage of my invention resides in the dualfunction of the pins, the pins acting both as supports for the wirewinding-and as contacts.

With-the above neral objects in view and others which wille obvious tothose skilled in the art from the description hereinafter, In inventionconsists in the features, details ofy construction and combination ofparts which will rst be described in connection with the vaccompanyingdrawings and then particularly defined in the claims.

In the drawings:

Figure 1 is a side elevation of the apparatus, parts being in section,and

Figure 2 is a plan view of the lower side of the rheostat.

Two l insulating discs 1, 2, are held in spaced relation by means ofshoulders 3, 3, formed on the spindle bearing 4. Adjacent the peripheryof each of these discs is a series of escutcheon pins 5, and theresistance wire 6 is progressivel laced between the two discs, passingun er the heads of the escutcheon pins. The pins also act as contactmembers.

The discs and the resistance wire winding carried thereby, may besecured to a micarta panel 7 by any desirable means such as by screws(not shown) passing through the upper disc andinto the panel, spaclngwashers 8 surrounding the screws. If desired, spacing members 9 may alsobe inserted between the discs.

A spindle 10 passes through the spindle' vbearing 4 and (panel 7, andsecured thereto at its upper en is a pointer 11 .and an ordihard rubberoperating knob 12.

11B/ w ashers 13 are mounted on the lower portion of the spindle whichmay be reduced as shown, and between these washers the contact brush 14is positioned. A nut 15 secures these members in place.

The terminals of the rheostat are indicated by numerals 16 and 17, aflexible metallic conductor 19 connecting the latter terminal with thebrush. Numeral 18 refers to blank contacts.

The o eration of the device will be obvious. y rotating the operatingknob 12 the brush 14 will be caused to travel over -the contactpins1andcut in the desired amount of resistance, the pointer 11indicating the position of the brush.

A rheostat of the character described is I very compact and permitssplendid ventilation -thereby preventing undue heating.

While I have shown and described only one contact brush and that locatedon the under side of the apparatus, it will be apparent, of course,that, with slight modifications in the mode of attaching the rheostat tothe panel, the brush could be positioned on the upper side of therheostat, or if desirable, two brushes may be used, one on each side. Bysuch an arrangement finer adjustments could be obtained as it would bepossible to secure contact at each half turn of wire. l y

Having fully described my invention what I claim as new and desire tosecure by Letters Patent is:

1. A rheostat including spaced members, resistance wire laced betweenbut outside the peripheries of said members, and means for holding saidresistance wire in place.

2. A device of the character described including spaced discs,resistance wire laced between said discs, and conductive means ixed'tosaid discs over which said Wire is uninterruptedly laced.

3. A device of the character described including spaced discs,resistance wire laced `between but outside the peripheries of saiddiscs, and a rotatable brush for variably utilizing the resistance ofsaid wire.

4. A rheostat including spaced members having contact pins arrangedadjacent the peripheries of said spaced members, resistance wire lacedbetween the spaced members and around the pins, and a movable brush formaking a, variable connection with the p 5. A device of the characterdescribed including spaced discs, contact pins arranged adjacent theperipheries of said discs, resistance wire laced between the discs andaround the pins, the pins acting both as an electrical connection and asa support for the wire, and a rotatable brush for making a variableconnection with the ins.

6. A rheostat including a spmdle, means for rotating the spindle, abearing for the spindle, said bearlng rovided with shoulders, discscarried by t e bearing and spaced by said. shoulders, contact pinsarranged adjacent to the peripheries of the discs, resistance wireprogressively laced between said discs and around the contact pins. abrush carried by the spindle for making a variable contact with thepins, and a. flexible metallic conductor connecting the brush with oneof the rheostat terminals.

7. A rheostat including spaced members, a continuous wire of uniformresistance laced between said members, and means for utilizing each turnof said lacing as a progressive step in the resistance characteristicsof said rheostat.

8. A rheostat including spaced members, a continuous uniform resistancewire uniformly laced between said members, and means for utilizing eachsection of said lacing as a resistance element in a rheostat ofuniformly progressive characteristics.

9. A rheostat comprising spaced rows of conductive elements and a lengthof resistance wire uninterruptedly laced between the elements of saidrows and in electrical contact therewith.

10. A device of the character described comprising spaced rows ofconductive elements and resistance wire stretchedly laced between theelements of said rows and in contact therewith.

11. A rheostat comprising spaced rows of elements supporting resistancewire uninterruptedly laced therebetween, a movable contactor toprogressively make Contact with any desired number of said elementscooperatively arranged to conduct electrical currents from said wire tosaid contactor.

W. STUART WEBSTER.

